Performance analysis on transmission of M-QAM HDTV signals in FTTF network with EDFA

Transmission of 60 channels M-QAM HDTV signals in the CATV fiber-to-the-feeder (FTTF) network is investigated. The authors consider the 1550 nm system with the Er-doped fiber amplifiers (EDFA). They analyze the system performance by considering all noise terms, and nonlinear distortions from laser, fiber dispersion, EDFA gain tilt and chirping. The results show there exists the optimal optical modulation index for achieving the maximum fiber span under the required bit error rate. The 1550 nm system with EDFAs shows its benefits for the distribution of M-QAM HDTV signals in CATV networks. Using one DFB laser with 5 dBm output and one EDFA with 15 dBm saturation output power shared among 10 feeders, the maximum fiber span can be 32 km for 256-QAM signals and 58 km for 64-QAM signals.>